Introduction
On September 11, 2001, New York City was attacked by terrorists, killing some 2,800 innocent people from 115 countries. The pain and anguish reverberated around the globe. The attack on New York City, home to many cultures and a center of world trade and finance, seemed an attack on the modern world.

The World Trade Center (WTC), 16 acres covering 12 city blocks plus other buildings in the surrounding area, was destroyed. This action had a staggering impact on the lives of people who live and work in Lower Manhattan and on New York City’s economy. Thirteen million square feet of office space was demolished and nearly seventeen million square feet of office space was damaged, and over six hundred thousand square feet of retail was lost (Figure 1).

Figure 1. Aerial photograph of the World Trade Center site and
surrounding area immediately after the attack.

Eighty-three thousand jobs disappeared in Lower Manhattan. Many businesses and residents left. Most of those who lost their jobs earned less than $25,000. There were two entry-level service employees (restaurant, sales clerks, and maintenance workers, etc.), for every one high-income employee.

Twelve hundred to two thousand small businesses were ravaged. Sales volumes of the remaining ones have dropped by up to 80%. Consequently, the surviving retail, service firms, and restaurants that survive are struggling¹ (Alliance for Downtown NY, 2002) (Figure 2).

Figure 2. Assessment of the extent and type of damage. An area
of 2 miles was affected.

Stations for three subway lines and the PATH train linking New York and New Jersey were leveled. These had carried thousands of workers daily from the New York City boroughs, New Jersey and Connecticut to the WTC site.

Civic Response After the Disaster
Civic organizations voluntarily banded together to formulate public policies that could restore normal living and working conditions in the area and guide the rebuilding. Some, like Rebuild Downtown Our Town (R.Dot), were formed specifically for that purpose. Others had been lobbying for many years for specific city and regional improvements, such as mass transit, housing, parks and public spaces, waterfront development, economic and social justice, and good urban design. The USA mainland had never been attacked before. The anguish and trauma resulting from the event motivated an intense citizen response.

Organized by the author² and Susan Szenasy³, R.Dot was formed immediately after 9/11 to give the Lower Manhattan community a civic voice. It is comprised of Lower Manhattan residents, business people and business associations, community advocates, artists, colleges, and academic and design professionals, as well as city officials and public appointees. The coalition meets regularly to discuss, research, and develop a collective vision that can shape the new downtown. Through its member groups, R.Dot represents the voices of thousands of people who have been directly affected by the destruction of the WTC.

Background
Lower Manhattan is the historic heart of New York City. During the American Revolution, New Yorkers burned the city to the ground in order to save it from British occupation. At its center is Wall Street, the historical center of America’s financial world.

Designated a special historic district by the city, Lower Manhattan’s narrow streets and crooked blocks predate the automobile. These are edged by a mix of many low-scale historic buildings, churches, graveyards, and tall 20th century buildings. West Street (a six-lane highway) borders the southern tip of the triangle-shaped district, which includes the historic commercial core of New Amsterdam (New York’s original name), Wall Street banking and commercial center, and the Battery where cannons once protected the harbor.

Adjacent to this district is Battery Park City, which was built in the 1980s in the areas where commercial ships once docked. Constructed on landfill formed in part by the dirt dug up from the WTC site, it is a major residential, business and recreation area. North of the WTC site is the city’s civic center and TriBeCa, an affluent family neighborhood consisting mostly of converted and elegantly rehabilitated warehouses and industrial buildings. To the east are the South Street Seaport, (another historic district), and Chinatown.

To form the World Trade Center, 12 historic blocks were bulldozed and combined to form a single super block. Three streets running north to south were blocked and two streets running from east to west were truncated. The WTC site was an anomaly in both its heartless destruction of historic sites and the audacity of its towering heights. That audacity came to symbolize New York City (and America) as a global center of business and finance.

As New Amsterdam expanded north, the size of its streets and blocks became larger and, consequently, so did the mass and size of its buildings. Elegant skyscrapers like the Woolworth Building sprung up in the early 1900s, creating a lively contrast with the older structures. This mixture of height and mass still characterizes Lower Manhattan. It is within the context of these images that we considered the revitalization of Lower Manhattan, the reconstruction of the WTC site and other destroyed buildings.

Societal Changes
Downtown began to decline as an office center in the 1920s and 1930s. The WTC was built to reverse that trend but it was unsuccessful. From the late 1970s to the early 1990s, astute property owners converted many buildings to residences. Together with the conversion of the surrounding industrial buildings into artist lofts, family-sized apartments, and the construction of Battery Park City, a new residential downtown was born alongside Wall Street. Before 9/11, the quality of life in this new, emerging 24/7 community was negatively impacted by a lack of civic amenities and integrated transportation. It was a fledging, mixed-use community caught between urban land uses of the 20^th century and the emerging ones of the 21^st century.

The needs of the 21^st century city society differ from those of the late 20^th century city in three major ways: economic and social changes due to globalization, the beginning of a knowledge-based economy, and the gender equality of the workforce.

The positive and negative effects of globalism and the new worker have been discussed in many recent books, including those by sociologists Manuals Castells and Saskia Sassen and economists Robert Reich, Peter Drucker, George Gilder and others.

This new economy, made possible through globalization and technology, requires intellectually-skilled and technologically-adept citizens. The emergence of service industries as a primary source of wealth production has changed the characteristics of the workforce from a task-based to a knowledge-based one. Society has become increasing mobile, cutting across barriers of language and culture. Competition for wealth producing talent crosses national and international borders.

Creative people are drawn to New York, like other global cities, where they find a synergy of common personal and professional interests and complementary skills that allow them to be successful.

The third change, and perhaps the most important one from the viewpoint of land use, is the percentage of women in the workplace. Women now comprise 46% of the American workforce⁴ (Hudson Institute, 1997). Two-wage families total 55%.

Women now garner 55% of bachelor's degrees, 53% of master's degrees, and nearly 40% of doctorates.⁵ (Hudson Institute, 1997). Women's ownership of small businesses escalated from 5% in the 1970’s to 38% in the 1990’s.⁶ (New American Evolution, 1998). Approximately 64% of all married women in the workforce today have children under six years of age.⁷ (Hudson Institute, 1997). School construction is an essential part of a mixed-use, urban communities. Land-use patterns must fit the needs of today’s working women, who still perform most of the household duties in addition to their work.

These three movements strongly suggest the formation of a series of community nodes where all of the elements of daily living (retail services, personal services, schools, playgrounds, health care, etc) are conveniently located within walking distance.

Additionally, the city must absorb into its overall fabric the disadvantaged groups caused in part by these movements. I believe that social, economic and environmental justice depends heavily on mass transportation, as well as incorporating a percentage of low to moderate income families into every community node. The lesson learned from 9/11 is that in cases of disaster and when mass transit is disrupted, service people are critically needed. Firefighters, police, laborers, and food suppliers must live in close proximity in order to provide immediate help. This argues for a mixed-income community.

Vision for the Future
The wide spread damage of Lower Manhattan below Canal Street offered an opportunity to create a vision of Lower Manhattan as a sustainable 21st century environment that symbolizes humanistic values.

New York City is organically clustered into neighborhood nodes, each with its own identity. While neighborhoods are typically formed by market-driven forces, present and past, a plan to rebuild Lower Manhattan requires a vision of what motivates people to create their neighborhood. This vision will determine the type of public investment that will guide its social and economic composition.

R.Dot’s coalition's objective is to support an imaginative design that creates the possibility of an inclusive, 24-hour residential and business community. It is necessary that the built environment attract and serve people who provide the intellectual, entrepreneurial, creative, and technological capabilities that empower New York City's society, its economy and the richness of its multi-cultural life.

R.Dot, along with 80 other organizations, formed the umbrella group, the Civic Alliance to Rebuild Downtown New York, which is administered by the Regional Plan Association. In February 2002, R.Dot published a white paper, "Rebuilding Lower Manhattan and the World Trade Center" (Willis 2002).⁸ R.Dot contributed to " Planning Framework: A Draft Report of the Civic Alliance to Rebuild Downtown New York", which was first published by the Civic Alliance in April 2002.⁹ On July 2, 2002, R.Dot published a position paper entitled Youth Council — Building for Future Generations,¹⁰ (Artigiani 2002) followed by a second position paper on June 15, 2002, Managed Streets: Street Life is Crucial to the Revitalization of Lower Manhattan (Oppenhiemer, Willis 2002).¹¹

Whether or not these efforts will influence final government policies has yet to be determined. Since 1922, nine master plans have been developed for Manhattan. Seven were developed by civic organizations, some in collaboration with the planning department. None has ever been adopted. New York City does not have a master plan.

Creating a Sustainable Environment
Rebuilding means rethinking how Lower Manhattan should physically, economically and socially function in a 21^st century context and how the WTC site could be redesigned in a sustainable way. Two documents, a Statement of Guiding Principles and an Urban Design Armature for Rebuilding Lower Manhattan were initially used to explore new possibilities.

Figure 3. Guiding Principles for Rebuilding

Figure 4. Design armature for use in developing conceptual urban designs.

In a review of several books on the topic of "sustainability", Steven Moore (Journal of Architectural Education 2000) points out that there are substantial differences in the use of the word. He explains "nor do the terms "eco-tec", "green", "regenerative, "ecological," or "bio-climatic" architecture provide a more precise meaning".¹² He gives examples of several viewpoints: Catherine Slessor, Eco-Tech (1997), argues that the ecological hypothesis is a style.¹³ James Steele in Sustainable Architecture (1997) believes that the ecological hypothesis is a political and economic doctrine.¹⁴ David Lloyd Jones in Architecture and the Environment (1998) argues that the ecological hypothesis requires retrieval from the radical fringe.¹⁵ In The Technology of Ecological Building, Klaus Daniels (1997) focuses on a set of empirically tested construction practices.¹⁶

Katie Williams, Elizabeth Burton and Mike Jenks (2000) point out that "a prerequisite to achieving sustainable urban form is knowing what it is. To realize the "sustainable city" there has to be a clear and commonly-held concept of what it will look like, how it will function and how it will change over time."¹⁷

The definition of "sustainability" used in this paper does not define sustainability of either the city or its buildings. It straddles several of the above definitions. The findings expressed here represent the ideas of a group of civic activists, including several well-known urbanists and designers¹⁸ who are lobbying to make Lower Manhattan a more livable place.

Human Sustainability
Thousands of people rushed to the destroyed area to help in the rescue attempt and to recover the bodies of the dead. Remains were found of approximately 39% of those who died when the WTC was destroyed. The explosion vaporized bodies, paper, and sections of the buildings, furnishings and equipment, mixing all into a fine white dust that penetrated every micro-inch of the surrounding offices, dwellings, and stores. No scientific analysis or regulatory standards existed for eliminating this dust and mitigating its impact on air quality. Fires continued to burn for almost three months after the attack.

Consequently, human sustainability set the public tone for recovery efforts in Lower Manhattan. It was paramount in discussions with rescue workers, residents, employees, and families of the victims. So too were issues like eco-sustainability, CO2 emissions, and stringent environmental guidelines for air pollution caused by transporting debris during the nine month-long rescue efforts.

Infrastructure for People
Lower Manhattan is a city within a city. Although it is dense and compact, it is not considered sustainable due to its lack of civic amenities and open space. It is the third largest downtown in the USA after Midtown Manhattan and Chicago. Prior to 9/11, the residential population was almost 42,000 residents and growing.¹⁹

R.Dot defined "infrastructure" to mean an armature that integrates all of the public parts of the community. The rationale was that people are its consumers. The types of infrastructure that are needed in Lower Manhattan must come from the habits and values of those who will use it: residents, employers, employees, visitors, and tourists. Infrastructure must be able to accommodate the needs of the present while being flexible enough to change with the future needs of the community.

This definition stemmed from the belief that the functions of infrastructure are driven by people's activities: eating, sleeping, communicating, interacting, conducting business, pleasurable pursuits, making art, partaking in or watching performances, thinking, playing, sports, and relaxing. People create communities, which evolve from their activities, needs, values and desires. To demonstrate how these activities affect ideas about infrastructure and land use, industrial designer Roland Gebhardt, co-chair of R.Dot’s infrastructure committee, created a series of "experience maps" showing how people in different lines of work used the city’s infrastructure (Figure 5).

Figure 5. Maps show how different types of individuals use the downtown area.

"Cities have to be places where people want to live. Unless cities are perceived as high quality environments, there is little chance that they will ever be sustainable"²⁰ (Williams, Jenks 1996).

A Changing Identity and Diversified Employment
Tall buildings define New York City’s urban landscape and create its identity. It has been said that while other places have their towering trees, New York has its towering buildings.

In the 1970s, as a result of the decline of downtown, the flight to the suburbs, and other economic factors, New York City faced bankruptcy. A vertical city like New York must have enough environmental and civic amenities to attract and keep people of all ages and family formations.

Since the 17^th century, Lower Manhattan’s identity has been based upon trading and banking. In the 20^th century, many financial companies moved to the city’s Mid-town, a mixed-use business center with its newer transportation and infrastructures, as well as other regional locations. Occupancy rates of financial companies on Wall Street declined.

As a result of 9/11, financial companies located downtown are spreading their financial operations across more than one location. Decentralization ensures that if one part of the company is destroyed, the rest of the company can carry on its work. This has further eroded downtown’s office building occupancies.

New York economists Alice Rivlin and Rosemary Scanlon concluded that financial services will continue to be an important component of Lower Manhattan’s economy, but their size and functions could change considerably after 9/11. They explain that "the continued diversification of the area into a more mixed-use, economically integrated community is both likely and desirable". "Lower Manhattan’s identity may be altered as other knowledge-based industries have the potential to rapidly expand as a driving force in the area's economy. Culture and tourism have considerable growth potential from both foreign and domestic visitors. The citywide demand for housing is likely to fuel a continued expansion of Lower Manhattan residential population, but both its rate of growth and composition will depends considerably on housing policies and land use decisions."(Rivlin et al 2002).²¹ Housing policies should subsidize low to moderate incomes housing units to achieve adversity of incomes, ethnic, and age groups.

They point out that "transit enhancements" will be the most important determinant of the size of Lower Manhattan’s employment base and office market. The extent to which this network is restored, improved, and expanded will largely determine how many workers the district can support."²²

Transportation
Lower Manhattan is one of the most concentrated business districts in the world, but its transportation infrastructure has not been substantially upgraded for nearly six decades. Existing mass transit systems have enabled Lower Manhattan to be more accessible to New Jersey residents than to New Yorkers, accounting for the high percentage of New Jersey residents working in Lower Manhattan. Eighty per cent of all trips to the area are made via public transport.

New infrastructure should include a multi-modal hub with long distance rail lines, subways, buses, water ferries, transit, and airport connections that will create locational demand for Lower Manhattan. Because Manhattan is an island, new ferryboat access to piers in Manhattan were immediately constructed. Now outer boroughs and states like New Jersey and Connecticut is a 5 to15 minute ride away. The expanded ferry system is carrying passengers who once arrived at the now demolished subways and PATH stations before 9/11.

Streets define the character of a city. In Lower Manhattan, the size, congestion, access, and connectivity of the streets dictate the urban environment. Streets are critical to an urban quality of life. Foot traffic sets the stage for social interactions: shopping, dwelling, eating, traveling, looking, and pausing for a chat. Lively public activities encourage healthy economic conditions, which have a profound effect on the economic wellbeing of a city and its ability to provide for personal security, parks, landscaping and flowers, clean streets, and regular garbage collection.

Street-level pedestrian vitality must be given the highest priority to encourage residents and businesses to remain in the area and attract tourists. The typical Manhattan streetscape consists of walkable streets lined with retail stores, restaurants and cafes with few overpasses and underpasses.

Other issues include road safety (especially for children), noise, air pollution, dirt, and traffic congestion. In an area with tall buildings and narrow streets, pedestrians at certain times of the day flood the streets, leaving little room for automobile passage. Trucks double park, blocking traffic, as there is little accommodation for off-street parking.

This paper argues for managed streets (scheduled automobile use) within the historic district and the WTC site, coupled with limited parking off of the ring road comprised by FDR Drive, West Street, and West Side highways that circle three edges of Lower Manhattan. New York City attempts to discourage the use of automobiles by limiting parking, charging high parking and toll fees, providing an ample supply of taxicabs, and encouraging mass transit. Alternate forms of surface movement and pedestrian traffic must also be interwoven into the transit system.

Urban Form
The attractiveness of Lower Manhattan and its design will depend upon the character of its urban form and scale, such as its block sizes, the diversity of building types, and architectural styles. Equally important are civic amenities, (schools, health, and culture); the character, size, and diversity of parks and grounds; waterfront access and view corridors, that attract private development (housing, offices, retail, and entertainment).

Communication
The WTC attack destroyed power lines, hard wire connections, and a regional broadcasting station. In the weeks immediately following the attack, business and individual communication relied on wireless cell phones and internet. "Extension cords" were laid on the surface of miles of streets (covered by a small mound of asphalt) in order to immediately reconnect power, electrical, telephone, and broadband systems until they could be installed permanently. September 11 demonstrated the need for comprehensive back-up systems that can withstand catastrophic failure.

Nature and Buildings
Reconstruction provides an opportunity to rebuild using the best technologies in sustainable planning, building design, and energy efficiency. The question is–does the political will exist to overcome the current state of reluctance by some developers to use such technologies? Most New York civic groups are committed to lobbying the government to mandate high performance and green building practices that seek to reduce environmental impacts while increasing the well-being of occupants and saving over-all life-cycle costs. Projects that design-in optimal building performance, such as investments in energy efficiency, day lighting, and good indoor air quality, provide human resource returns in terms of occupant health and productivity. They also can improve the effectiveness and long-term value of real estate.

Civic groups request that the redevelopment of the World Trade Center site achieve zero-net CO2 emissions for energy used at the WTC site and a rating of platinum under the LEED (Leadership in Energy and Environmental Design) program of the U.S. Green Building Council.

Use nature to power buildings and mitigate atmospheric heat; green buildings and the land; create public spaces at the ground level for parks and areas with heavy planting; and incorporate private green spaces within buildings, such as courtyards, terraces or planted roofs. These measures help reduce building heat, which contributes to global warming (the heat island effect), and the storm water flow volumes into municipal drainage systems.

Other changes can be made on a larger scale: recognize the importance of Lower Manhattan’s waterfront for parks, recreation, and boating; provide public access to the waterfront by extending both Battery Park along the East River and the Hudson River Park; designate the area carbon-neutral; and require that CO2 emissions are substantially offset by carbon absorbing plantings. High-efficiency centralized systems using co-generation technology support mixed-uses and 24-hour activity. They also reduce dependence on oil and fossil fuels.

Enforcement of Sustainable Legislation
It is important that lawmakers use regulatory powers to mandate the application of environmental design guidelines; that the existing Battery Park City Authority Environmental Design Guidelines govern all construction; and LEED certification, a national standard for green buildings for all new construction, be required.

Community Node Organization
A planning node consists of a population large enough in number to create a self-contained community that is eligible for schools, health care, police, fire protection, postal services, banking, and open spaces for playgrounds and parks. It is small enough that professional and commercial services are within walking distance and that delivery services are available for groceries, ordering-in restaurant food, laundry, etc.

Interconnected community nodes grow organically around mass transit stops. The larger the transportation network, the more populated and diverse the community is likely to be (Figure 6).

Figure 6. General locations of transportation nodes that stimulate
organic community growth.

In Manhattan’s vertical urbanism, a community node of high and mid-rise building usually includes offices, or apartments, or hotels–all with retail at ground level and with limited parking facilities. Some of these buildings may contain schools and health facilities (Figure 7).

Figure 7. A conceptual idea of how nodal development of a self-contained
neighborhood can evolve.

Tall buildings result from the desire of many people to live and/or work in the same location. People choose places for a variety of reasons — to mix with people sharing work; cultural or entertainment interests; to live near the woods, mountains, or the beaches; or to enjoy a certain type of climate.

Whatever the motivation, towering residential and office buildings are attractive to a large number of people. In conjunction with a willingness to live vertically, people make practical decisions about the quality of urban life and employment, as well as the availability and cost of housing, schools, health care, recreation, and entertainment.

In an urban area, it is the small quality-of-life things that make life acceptably livable. Personal uses should be a maximum of a 10 minute walk. Mass transportation should provide access to museums, performing centers, sports venues, and government services that may be located cross—town from the community node.

Market-driven private investment will organically attach itself to the armature (transit, housing, schools, health services, open space, and water front access) created by public investment and policy. The concept of organic mixed-uses differs from post-war idea of planned multiple uses in one building or complex.

Conclusion
Civic action was galvanized to help form public policy (as opposed to simply commenting on the government’s proposed plans) and to be involved from the beginning in the revitalization of Lower Manhattan’s damaged communities. New Yorkers were emotionally, functionally, and financially engulfed in the tragic aftermath of 9/11. One of our major objectives was to demonstrate that a more democratic, global, creative, socially integrated, and economically productive - 21^st century community could grow organically from the ruins.

End Notes
¹Alliance for Downtown NY, Inc. (2002). Downtown Alliance Survey of Lower Manhattan Retail Establishments January 2002. New York: Alliance for Downtown MY, Inc.

²Beverly Willis is President and Director of the Architecture Research Institute, Inc., a think-tank whose mission is livable cities.

³Susan Szenasy is Editor-in-chief of Metropolis magazine, which publishes articles on well-designed objects, spaces, and buildings with an emphasis on sustainable concepts.

⁴Hudson Institute. (1997). Workforce 2020:Work and Workers in the 21st Century, Indianapolis: Hudson Institute, p. 53.

⁵Hudson Institute. (1997). Workforce 2020:Work and Workers in the 21st Century. Indianapolis: Hudson Institute pp. 52,53.

⁶Small Business Administration. (1998 June). New American Evolution: The Role and Impact of Small Firms, www.sba.gov/ADVA/stats/eval_pap.html:, p. 12.

⁷Hudson Institute. (1997). Workforce 2020:Work and Workers in the 21st Century, Indianapolis: Hudson Institute, p. 53.

⁸Willis, Beverly. (2002, February 15). Rebuilding Lower Manhattan and the World Trade Center, New York: Rebuild Downtown Our Town.

⁹Civic Alliance to Rebuild Downtown New York. (2002, April 26). A Planning Framework: A Draft Report of the Civic Alliance to Rebuild Downtown New York, New York: Civic Alliance to Rebuild Downtown New York.

¹⁰Artigiani, Carole. (2002. July 3). Youth Council: Building for Future Generations, New York: Rebuild Downtown Our Town.

¹¹Oppenheimer, Brent, Willis, Beverly. (2002, June 15). Managed Streets: Street Life is Crucial to the Revitalization of Lower Manhattan, New York: Rebuild Downtown Our Town.

¹²Moore, Steven A. (2000). A Review of the Technology of Ecological Building. Journal of Architectural Education, May, p. 246.

¹³Slessor, Catherine. (1997). Eco-Tech: Sustainable Architecture and High Technology. London: Thames and Hudson.

¹⁴Steele, James. (1997). Sustainable Architecture, New York: McGraw Hill.

¹⁵Jones, David Lloyd. (1998). Architecture and the Environment: Bioclimatic Building Design. Woodstock, NY: Overlook Press.

¹⁶Daniels, Klaus. (1997). The Technology of Ecological Building- Basic Principles and Measures, Examples and Ideas. Trans. Elizabeth Schwaiger. Basel and Boston: Beirkhauser.

¹⁷Williams, K, Burton, E. Jenks, M. (2000). Introduction ­ Defining Sustainable Urban Form, eds. In Achieving Sustainable Urban Form, London: E&FN Spon, p. 7.

¹⁸Jean Gardner, Professor, Parsons School of Design; Rafael Pelli, Principal, Cesar Pelli & Associates; Ted Liebman, Partner, Liebman-Melting Partnership Architects; and James Biber, Principal, Pentagram.

¹⁹U.S. Census Bureau. (2000). Population Tracts for Lower Manhattan, U.S. Department of Commerce: Washington DC.

²⁰Williams, K., Jenks, M. and Burton, E. (1996). Urban Consolidation and the benefits of intensification, p.18, 2000. Compact Cities: Sustainable Urban Development. ed. Gert de Roo and Donald Miller, Aldershot, UK: Ashgate.

²¹Civic Alliance to Rebuild Downtown New York. (2002, April 26). A Planning Framework: A Draft Report of the Civic Alliance to Rebuild Downtown New York, New York: Civic Alliance to Rebuild Downtown. (see Riviin, Alice, Scanlon, Rosemary, quotes p.13).

²²Civic Alliance to Rebuild Downtown New York. (2002, April 26). A Planning Framework: A Draft Report of the Civic Alliance to Rebuild Downtown New York, New York: Civic Alliance to Rebuild Downtown. (see Rivlin, Alice, Scanlon, Rosemary, quotes p.14).